Since the switch from fixed point to floating point, and the introduction
of CoglFixed, ClutterFixed has been typedef'd into a float. This makes
ClutterFixed the worst fixed point API ever.

Now that Clutter has been migrated to CoglFixed and gfloat whenever needed,
ClutterFixed can be safely removed.

The only thing that Clutter should still provide is ClutterParamSpecFixed,
for installing fixed point properties into GObject classes.

The ClutterFixed symbols have been entirely removed from the API.